Influence of Different Substrates on the Production of a Mutant Thermostable Glucoamylase in Submerged Fermentation

Autor(es)

Pavezzi, Fabiana Carina ^{[1, 2]} ; Jacomassi Carneiro, Andreia A. ^{[1, 2]} ; Bocchini-Martins, Daniela Alonso ^[1] ; Alves-Prado, Heloiza Ferreira ^[3] ; Ferreira, Henrique ^[4] ; Martins, Paula M. ^{[4, 2]} ; Gomes, Eleni ^[1] ; da Silva, Roberto ^[1]

Afiliação do(s) autor(es)

^[1] UNESP Sao Paulo State Univ, Biochem & Appl Microbiol Lab, BR-15054000 Sao Paulo - Brazil

^[2] UNESP Sao Paulo State Univ, Inst Biol, Sao Paulo - Brazil

^[3] UNESP Sao Paulo State Univ, Food & Tecnol Dept DFTASE, Sao Paulo - Brazil

^[4] UNESP Sao Paulo State Univ, Univ Pharmaceut Sci, Dept Biol, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Applied Biochemistry and Biotechnology; v. 163, n. 1, p. 14-24, JAN 2011.
• Citações Web of Science: 8
• Assunto(s): Enzimas Amidos e féculas Aspergillus

Resumo

Three mutations, Ser54 -> Pro, Thr314 -> Ala, and His415 -> Tyr, were identified in Aspergillus awamori glucoamylase gene expressed by Saccharomyces cerevisiae. The mutant glucoamylase (GA) was substantially more thermostable than a wild-type GA at 70 A degrees C, with a 3.0 KJ mol(-1) increase in the free energy of thermo-inactivation. The effect of starch from different botanical sources on the production of this GA was measured in liquid fermentation using commercial soluble starch, cassava, potato, and corn as the carbon source. The best substrate for GA production was the potato starch showing an enzymatic activity of 6.6 U/mL. The commercial soluble starch was also a good substrate for the enzyme production with 6.3 U/mL, followed by cassava starch and corn starch with 5.9 and 3.0 U/mL, respectively. These results showed a significant difference on GA production related to the carbon source employed. The mutant GA was purified by acarbose-Sepharose affinity chromatography; the estimated molecular mass was 100 kDa. The mutant GA exhibited optimum activity at pH 4.5 and an optimum temperature of 65 A degrees C. (AU)

• Processo FAPESP: 02/08355-8 - Melhoramento da termoestabilidade da glucoamilase de aspergillus awamori pela tecnica de pcr mutagenico, purificacao e caracterizacao da enzima.
• Beneficiário: Roberto da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 07/07930-2 - Glucoamilases mutantes termoestáveis do fungo Aspergillus awamori expressas em levedura Saccharomyces cerevisiae: seqüenciamento do gene, produção e purificação da enzima obtida por fermentação submersa
• Beneficiário: Fabiana Carina Pavezzi
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 07/08083-1 - Avaliação da atividade prebiótica de gluco-oligossacarídeos obtidos a partir de beta-glucanas de Agaricus blazei.
• Beneficiário: Andréia Aparecida Jacomassi Carneiro
• Modalidade de apoio: Bolsas no Brasil - Doutorado